The printing on both sides of flat substrates, for example, of paper, also referred to as duplex printing, is known. In this situation, the substrate is printed on two mutually opposed sides.
The principle is further known of printing three-dimensional objects, in particular containers, in particular with a printing method in accordance with the ink-jet principle.
With three-dimensional containers the problem arises that the wall can only be printed on one side, since the second side of the wall faces towards the interior of the container, and delimits this on the circumference side. Printing on both sides of the container wall would be desirable, however, since either after the emptying of the container with non-transparent contents or, with transparent contents, also with the filled container, the inner side of the container wall could be used for the application of a design element and/or information.